The use of light-emitting diodes (LEDs) is employed for a variety of illumination applications. As LEDs have the advantages of providing a bright light, being reasonably inexpensive, and drawing very little power, LED lighting is continuously increasing as an alternative to traditional incandescent lighting. Furthermore, LEDs have a long operational life. As an example, white LED lamps may last 100,000 hours, which is approximately 20 times the operational life of an incandescent bulb.
However, in order to maintain a long service life and/or avoid damage of a lighting arrangement comprising LEDs, it is advisable that the construction of the lighting arrangement withstands mechanical stress due to the influence of temperature on the materials used in the lighting arrangement, such as e.g. high/low temperatures and/or temperature fluctuations. The temperature conditions may arise externally, e.g. from the lighting arrangement environment, and/or internally, e.g. from fluctuations in heat produced by the LEDs of the lighting arrangement during operation.
In patent document WO2010/032169, a light-emitting arrangement is disclosed, comprising a LED, a printed circuit board (PCB) having a electrically/thermally conductive portion, and a heat release member for dissipating heat generated by the LED during operation. During operation, the heat is transferred from the LED via the conductive portion of the PCB to the heat release member. More specifically, the LED is provided on a LED chip which in turn is arranged on a substrate, wherein an electric/thermal connection between the substrate and the conductive portion of the PCB is provided by electric contacts and/or thermally conductive glue. Hence, heat from the LED may be transferred along a heat transfer path to the heat release member, wherein a portion of the heat transfer path, from the LED to the PCB, comprises electric contacts and/or thermally conductive glue.
However, alternative solutions for an adaptation to temperature effects may be of interest.